An inflatable vehicle occupant protection device, such as an air bag, is part of an apparatus which further includes a crash sensor and an inflator. The crash sensor senses vehicle conditions that indicate the occurrence of a crash. When the crash sensor senses a crash-indicating condition of at least a predetermined threshold level, the inflator is actuated. The inflator then emits inflation fluid which inflates the air bag into the vehicle occupant compartment to help protect an occupant of the vehicle.
An air bag and an inflator are typically assembled together as parts of an air bag module which is separate from the crash sensor. The air bag module is installed in or on a part of the vehicle adjacent to the vehicle occupant compartment. In addition to an air bag and an inflator, an air bag module may include a reaction canister in which the air bag and the inflator are received. The reaction canister typically has mounting tabs with apertures for receiving fasteners that fasten the module in its installed position in the vehicle.